Abstract - The fossil record of coelacanths is patchy, with very few taxa known from the
Triassic of Asia. We report here two new genera and species of coelacanths from
the Luoping Biota, a recently found site of exceptional fossil preservation from
Yunnan, South China. The first new taxon, Luopingcoelacanthus eurylacrimalis, is
based on four specimens, which together show most aspects of the anatomy. One
specimen shows two small coelacanths inside the ventral portion of the abdominal
cavity, and these are interpreted as intrauterine embryos, close to birth size,
based on comparisons with previously reported embryos of the fossil coelacanths
Rhabdoderma and Undina, and the extant genus Latimeria. Our new find extends the
evidence for ovoviviparity in coelacanths back from the Late Jurassic to the
Middle Triassic. The second new taxon, Yunnancoelacanthus acrotuberculatus, is
based on one specimen, and differs from Luopingcoelacanthus in the dentary,
lachrymojugal, number of rays of the first dorsal fin, and especially in the
ornament on dermal bones and scales. A cladistic analysis shows that the new
taxa are closest relatives to the derived clade Latimerioidei. The relatively
high diversity of coelacanths in the Early Triassic, and adaptations of living
Latimeria to low-oxygen conditions, suggests that the group may have included
‘disaster taxa’ that benefited from anoxic and dysoxic ocean conditions in the
aftermath of the end-Permian mass extinction.

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About Me

My name is Bill Parker and I am a paleontologist in northeastern Arizona. While my day job mainly involves roaming the badlands of Petrified Forest National Park picking up bit after bit of phytosaur scrap (and finding some good stuff in-between), thus my main focus is the paleontology of the Triassic Period. However, I also have a very strong interest in Civil War history, and am a direct descendent of veterans who fought on both sides. Note: This is a personal site and all posts are my own opinions and do not represent the opinions of the National Park Service.